Im Trying to connect my server but it says Failed to connect to server: Unknown Host "ip"

Is there any way I could get help cause when I’m on the server jar everything is there for the server to work but what ip should i use on the server prop cause i tried using every single one IPv4 address along with my own ip address im also on the verison beta 1.0_01 and i tried using beta 1.7.3 is it because playit doesn’t support old versions? i just need some help figuring this out.

also i just realized my connection for my network to playit.ggs is working but when it network tries to connect for the shared ip it doesn’t work for some reason